1. Field of the Invention
The present general inventive concept relates to a radio receiving apparatus, and more particularly, to a radio receiving apparatus to prevent deterioration in radio receiving performance of an antenna due to noise generated from a printed circuit board provided in the radio receiving apparatus.
2. Description of the Related Art
Radio receiving apparatuses have convenient portability and serve to reproduce moving images, or other visual or audio information based on a radio signal received thereby. Examples of the radio receiving apparatuses include wireless portable communication terminals for receiving digital multimedia broadcasting (DMB), wireless internet signals, or Bluetooth® signals, and portable multimedia players (PMPs).
FIG. 1A illustrates a configuration of a conventional radio receiving apparatus 1. As illustrated in FIG. 1A, the conventional radio receiving apparatus 1 includes a body 3 defining an outer appearance of the radio receiving apparatus, a display 5 provided at a front surface of the body 3, a button array 7 provided on the body 3 at the side of the display 5 for manual operation of the radio receiving apparatus 1, an antenna 9 attached to a side surface of the body 3 for receiving a radio signal from an external station, and a printed circuit board (PCB) 11 on which a variety of devices, related to an operation of the radio receiving apparatus, are arranged.
Referring to FIG. 1B, the printed circuit board 11, which is provided within the radio receiving apparatus, includes a power plane 13 for the supply of power, a ground plane 15 spaced apart from the power plane 13, the ground plane 15 serving as a standard plane for power and signal distribution, and a dielectric layer 17 provided between the power plane 13 and the ground plane 15. A variety of operating devices 20 are arranged on the power plane 13 or ground plane 15. Also, for the flow of current and the transmission of signals, the power plane 13 or ground plane 15 is formed with a pattern (not illustrated).
If the radio receiving apparatus 1 operates, an electromagnetic field F is generated within and around the printed circuit board as illustrated by the arrows, thereby causing electromagnetic wave noise.
Here, the electromagnetic wave noise includes switching noise caused by On/Off operation of the variety of devices 20 arranged on the printed circuit board 11 and other noises caused, for example, by a current and a signal moving along the pattern formed on the printed circuit board 11.
The resulting electromagnetic wave noise causes electromagnetic interference (EMI) that has an effect on the antenna 9 used to receive an external radio signal. Consequently, the electromagnetic interference has the problem of deteriorating receiving sensitivity of the antenna 9.